CNN) — It's 24 years old this year, but the Boeing 777 airplane is still going strong -- it's one of the aviation manufacturer's best-selling models and is used by airlines across the world.But, after nearly quarter of a century of flying, the first 777 has made its final flight -- to an aerospace museum in Arizona, where it'll see out its retirement as a top travel attraction.The prototype 777-200, call sign B-HNL, rolled off the production line in 1994, eventually entering commercial service for Hong Kong's Cathay Pacific airline in 2000.Over the years it's clocked up 20,519 flights for Cathay. That's a whopping 49,687 hours of flying time.The venerable airplane was taken out of service in May 2018 and, after Boeing and Cathay agreed on the donation, it touched down in Tucson on September 19 to begin its new life at the Pima Air & Space Museum.